Experimental and Numerical Assessment of the Service Behaviour of an Innovative Long-Span Precast Roof Element

Abstract

The control of the deformative behaviour of pre-stressed concrete roof elements for a satisfactory service performance is a main issue of their structural design. Slender light-weight wing-shaped roof elements, typical of the European heritage, are particularly sensitive to this problem. The paper presents the results of deformation measurements during storage and of both torsional-flexural and purely flexural load tests carried out on a full-scale 40.5 m long innovative wing-shaped roof element. An element-based simplified integral procedure that de-couples the evolution of the deflection profile with the progressive shortening of the beam is adopted to catch the experimental visco-elastic behaviour of the element and the predictions are compared with normative close-form solutions. A linear 3D fem model is developed to investigate the torsional-flexural behaviour of the member. A mechanical non-linear beam model is used to predict the purely flexural behaviour of the roof member in the pre-and postcracking phases and to validate the loss prediction of the adopted procedure. Both experimental and numerical results highlight that the adopted analysis method is viable and sound for an accurate simulation of the service behaviour of precast roof elements.

Full-scale testing and numerical analysis of a precast fibre reinforced self-compacting concrete slab pre-stressed with basalt fibre reinforced polymer bars

“…A semi-analytical procedure based on a sectional approach for the evaluation of serviceability and ultimate limit state flexural behaviour of concrete elements pre-stressed with BFRP bars is proposed in the paper, whose predictions are validated through the comparison with the experimental results. A similar procedure for precast concrete pre-stressed with steel tendons was reported by Dal Lago et al [40].…”

Tension-only ideal dissipative bracing for the seismic retrofit of precast industrial buildings

“…The difference would basically rely only upon a higher clear height of the column enlarged by the beam depth, since the beam follows the rotation of the column element in this direction. The single frame model is to be considered appropriate whether one bracing system is installed on each two-directional frame, or whether a rigid diaphragm is provided by the structural layout, which is however rare for precast industrial frame structures (Dal Lago andFerrara 2018, Dal Lago et al 2019). Installing dissipative braces on single frames of a building with roof system with flexible diaphragm may jeopardise every beneficial effect, due to the ineffective restraining of the unbraced frames by the adjacent braced ones.…”

Slender precast voided slabs underwalking‐inducedvibration

“…Within the European scenario, the relentless quest toward daring precast decks, started in the 1950s, recently brought to the definition of standard production lines with span up to 42 m for roof elements. 1 Due to their peculiar slenderness, the critical design issue for these prestressed elements, which are also used as secondary beams in industrial single-storey frames, is frequently deflection control at the Serviceability Limit State (SLS) rather than resistance at the Discussion on this paper must be submitted within two months of the print publication. The discussion will then be published in print, along with the authors' closure, if any, approximately nine months after the print publication.…”